Ducky gets a new assistant, who should come in useful when the team find themselves up to their necks in an investigation involving a marine found impaled on a tree stump.
Castle and Beckett investigate the murder of a nanny in her 20s, who was found dead inside a dryer in the laundry room of an upscale apartment building in Manhattan.
The BAU head to Miami to investigate a serial killer with a seemingly conflicted sexual identity. JJ reconnects with a former colleague and a secret is revealed.
Bobby is nervous about meeting Athena's parents; Maddie tries to end her marriage for good; Doug tries to insinuate deeper into Chimney's life.
Intelligence are faced with several cases of gang-related child abductions. Halstead goes undercover to find a kidnapped boy.
